Oil-well jack



Feb. 22, 1927. 1,618,232"

F. H. scHwERlN on. WELL JAQK Filed Aug. 2. 1923- INVENTOR a; g/M.

' ATTORNEY Patented Feb. 22, 1927.

7 STATES.

fimiik q WE- m, WEST VIEW, rN XLVAN A; ASQ I N TO T DUFFI v or,manage-mare,

AW AQ RING; COMPANY, 0 PITT PENNSYLVANIA, a. COR'PWATIQN Orr-WELL JACK;

7 Aipi plicationfiled August 2, 1923. Serial N0'./655,1?5E-.;

The invention relates to oil well jacks for wrenching and unwreniching.the sectionsof the drills. In some cases the screw parts whenthey. haveremained jammed toget her become frozen, so that it is very dif ficultto disconnect them when desired by the ordinary ratcheting operation.The present invention aims toprovide a strong, reliable, easilyoperated' and powerful construction in connection with the back-post,

for starting the 'unwrenc hingoperation,

the traveling jacking post.

In" the accompanying drawing forming part hereof:

which may then be continued by means of Fig. 1 is a "perspective viewillustrating the useof the jack;

Fig. 2 is aside elevation of the improved back-post on the rail,portions being broken away and in section; and V Fig. 3 is across-section on the line 33 of Fig. 2.

An oil-well jack has a rail 1, usually bent into the segment of acircle, and having ratchet teeth 2 cut in the top of its head over themajor portion of its length. Slidable on the rack part of the rail is ajacking-post 3 containing singleor double-acting pawl mechanism operableby a lever bar inserted in a lever socket 4 to cause the post to advancealong the rail in a familiar manner;

In use one of a pairofwrenches 5 rests against the beak of thistraveling post, while the other wrench rests against a back-post. Thetwo wrenches grip adjacent drill sections 6, and in one arrangement ofthe wrenches ratcheting of the; traveling post will cause the sectionsto be screwed together, while by reversing the positions of the wrenchesthe same operation will cause above andtangential with respect-to thecurve offtheraill. Another post 9 of massive" construction, having a.beak the front; to. coact; with onebf the wrenches, ,is alsoengaged withthe rail," butin such manner; as I to be slidable. For this} purpose is,formed with lateral basal: slotted] and. flanged portions. 10, which.embraceaand' en'- gage under the head ofcthe; rail and areof such;l'engfthandconformation asatmafv. ford steadybearing I The slidableback-post thus-supported ;and guided, is sustained an diadapted tobe opeerated: by aiscrew 11 having ashaft portion, 12-. which is journaledin-the opening, through the fixed backrpo'st 8. A, collar on. the screwbearing against the fixed post holds the screwagainst-thrust, and ;atthe, opposite side of thegpost aratchet wheel 14 is fixed to theprojection of the shaft for operation by the pawl of a ratchet-leversocket 16, which is pivoted on the shaft.

The screw portion of the shaft passes through a nut 15 into a. cavity 17in'the slidable back-post 9, the nut being received in the outer part ofthis recess where it is sustained against thrust by a shoulder 18 on thenut. The cavity is made larger than the screw and nut, and the shoulder18 and the cooperating face 19 on the post block are made on a sphericalcurvature, giving'the effect of a' ball and socket. This prevents bind-.ing of the straight screw as it forces the slidable block to move on thecurved rack. and also allows for any inaccuracy in relation between theparts; Ribs on the block entering slots in the nut, as indicated at 20,prevent the nut from turningywhile permitting the desired flexibility.While the preferred formfof theinventio has been described in detail, itshould be understood that I do not necessarily limit myself totheprecise construction.

What I cla1m as new 1s:

1. In an oil-well jack having a rack rail 2. In an oil-well jack havinga rack rail and a traveling jacking post adaptedto be 7 slidable posts,

ratcheted along the rail, a back-post fixed on thelrail near one end,aslidable back-post having bearing engagement with the'rail in front ofthe fixed back-post, a screw operable by a lever toact between the fixedand a ratchet wheel fixed on the screw, and a pivoted ratchet lever.

3. A back-post for an oil-well jack, comprising a back-post adapted tobe fixed to the rack rail, a massive slidable back-postqhaving a beaktocoact with a wrench and; lateral basal guide portions adapted tofengagethe head of the rail so as to be guided and braced thereby, said.slidable' back-post containing a nut, a screw journaled in the fixedback-post and in threaded engagement with I the nut, and ratchet levermechanism for operating the screw.

'7 4:. In an oil-well jack having a rack rail and a traveling jackingpostadapted to be ratcheted along the rail, a fixed back-post on i therail, a movable back-post having sliding bearing on the rail in front ofthe fixed back-post, a screw held rotatably in the fixed back-post, aratchet lever tooperate the screw, and a nut for the screw flexiblyseated in the slidable back-post. v

5. In an oil-well 'ack having a rack rail and a traveling jacking postadapted to be ratcheted along the rail, a fixed back-post I bacl i-post, a screwheld 'rotatably in the fixed back-post, a ratchet lever tooperate the screw, said slidable back-post containing 'on the rail, amovable back-post having slidingbearing on the rail in front of the,fixed cavity having a curved seat at its entrance; 7

a nut having a curved flange bearing on the seat, and means to keep thenut from turn ing. v V V 6. In an o-il-wellnjack having an arcuate rackrail, a back-post fixed on the rail, a

engagement with the rail in front of the fixedv back-post, a nut in theslidable back-post, a

screw engaging said nut and havingthrust bearing against the fixedbjack-post and a gournal portion passing through SELlCl post,

a ratchet-wheel on the'projectionotsaid screw at the'bacl': ofsaid-fixed back post, and v a ratchet-lever pivoting about saidprojection.

FRANK n. :SCHWERIN.

